But even for those of us who know that, say, spaceflight is real, and the Earth is round(ish), this "evidence" can sometimes seem a little legit. Case in point:
If you've never stopped and thought about the curvature of the Earth, this question from former television personality Tila Tequila might have caught you off guard. It's the kind of question that plenty of people probably ask themselves — it's just that most of you shrug it off or turn to Google instead of deciding the Earth is flat.
Astronomer Phil Plait, who now has a blog over at Slate, answered this one back in the O.G. blogging days of 1997: Long story short, the Earth is a big place, and humans are tiny. Anything that fits into our field of vision is going to be so minutely curved that we won't be able to tell it's curving.
If the Earth was really tiny (say, a mile across), we'd see it rise before us and fall beneath us, and any skyscrapers would look positively tilted in relation to one another. But the Earth is nearly 8,000 miles across, with a circumference of 24,901 miles. That's a lot of space for the ground to curve on. It's way more subtle than we could hope to see with our puny human eyes.
If this is still confusing you, and your pride can handle the blow, "Highlights Kids" actually has a really nice analogy. It probably seems like I'm making fun of you, but I'm not: It's a really good analogy.
Tila probably won't dig our answer, because it's really easy to disregard scientific evidence that contradicts your personal beliefs. This is especially true when it comes to conspiracies. But I hope some of you sitting on the Flat Earth fence will be satisfied with this explanation.